从光纤陀螺光学系统缺陷角度,研究了由于光纤陀螺保偏光纤融接误差及光学器件的不完善引起的偏光干涉效应,理论分析并实验研究了偏光干涉效应对传输光谱的影响及其对光纤陀螺性能的影响。研究表明,在当前的技术条件下,偏光干涉效应对光纤陀螺的标度因数影响可以忽略,偏光干涉不影响一般意义下的光源相干长度,但是却导致光源相干特性的变化,反应在相干图上出现了多个干涉衬比度峰值,这会降低宽谱光源的短相干长度特性给光纤陀螺带来的好处,由此也说明不能仅由相干长度这一个参量描述光源的相干特性。

From the point of view of optic system limitation of fiber optic gyro, the phenomena of polarization interference which suffered from the fusion error of polarization maintaining fiber and unperfect optical element is studied. Also the effect of polarization interference on transmission spectra of light source and consequently on performance of the fiber optic gyro is discussed theoretically and experimentally. Under present technical condition, it is showed that the polarization interference does not affect the scale factor of fiber optic gyro. Although the polarization interference does not change the general coherent length of light source, it affects the interference characteristic of light source that there appear more than one fringes on the interference pattern. The additional interference fringes will shorten the short coherent length of wide band light source and benefit the fiber optic gyro. So it is improper not to describe the coherent characteristic of light source just by its coherent length.